How come when the Republicans lose an election—as in Barack Obama sweeping the presidency in a landslide—the Right Wing responds by saying: “This proves the Republican Party has to become more conservative.”

But when the Republicans win one—be it even a single Senate race—Democrats start rending their clothes and saying: “We’ve got to become more conservative.”

The Democrats are wimps, that’s how come.

There are myriad explanations for Martha Coakley’s defeat in the special Senate election to fill the late Ted Kennedy’s chair:

• She was a lousy candidate, clothed in arrogance and complacency, who took voters for granted and didn’t work hard enough. After winning her primary she took a vacation from the campaign, la-dee-dah.
• Her opponent, Scott Brown, was an exceptionally attractive candidate with Sarah Palin good looks and an appealing personal narrative. Also, he did work hard enough, traveling around in a pickup truck that he claimed had 170,000 miles on it. (I can just see Mitt Romney right now, hiring a team of drivers to get 200,000 miles on his pickup before the 2012 campaign.)
• The election was a referendum on the president’s health-care plan and it was rejected.
• The election was a referendum on Barack Obama and he was rejected.
• Massachusetts voters are selfish, irresponsible, and not to be trusted with the franchise. It was the place, remember, that hosted the Salem witch trials.

There’s some truth to all of these analyses—well, some of them anyway—but you can come up with just as persuasive a case for Coakley winning:

• Ted Kennedy had held that particular seat for 47 years at the time of his death and no Republican had been elected to the Senate in Massachusetts since 1972.
• Obama had carried the state a little more than a year ago by 26 points.
• To call Brown, a conservative Republican, “little-known” isn’t a wild exaggeration. He was a single-practitioner attorney and a practically invisible state senator. Six months ago, not one Massachusetts voter in 10 could have picked him out of a police lineup.
• Coakley may not have been the warmest, most energetic of candidates, but neither was she Lizzie Borden. She was, in fact, a fairly popular attorney general (winning the election in 2007 with 73 percent of the vote) with a long record of accomplishment as a public figure in her state.

So why did this upset (which must have sent Ted Kennedy whirling like a dervish in his grave) happen?

The Democratic Party, starting with the political wizards in the White House on down, simply blew it. It wasn’t just Coakley who took a vacation in the middle of the campaign, the entire party did.

Think of the stakes. Congress had arrived at the very cusp of passing health-care reform. Every vote, particularly in the Senate, was not merely important, but crucial.

Why would you allow a candidate of limited experience to conduct his or her own campaign in those circumstances? Why would you let her go on vacation?

The Democratic hierarchy should have kidnapped her, if need be, tied her to the back of a flatbed truck and driven her around the state to meet the folks. It should have engulfed her campaign with money. In other words, it should have practiced politics. It didn’t. I’m not sure the party knows how to anymore.

Now they’re whining about it, calling the unfortunate Ms. Coakley names.

The only sound worse than a Democrat whining about a loss is a Republican crowing about victory. Conservatives are famously sore winners, and their taunts and smug observations are hard for us poor liberals to take.

But take them we must; we have no choice. Obama and a few others are trying to make the best of things, saying that they’ll try harder to cobble together legislation on which a bipartisan coalition can agree.

Lots of luck, Prez.

Republicans want Obama to fail, and they just took a step toward fulfilling that wish.